Dehydration modifies somal CRH immunoreactivity in the rat hypothalamus: an immunocytochemical study in the absence of colchicine.

Corticotropin-releasing hormone immunoreactive (CRH-ir) neurons were examined in the hypothalamus of euhydrated and dehydrated rats without using colchicine. CRH-ir cells were observed in the lateral hypothalamus, retrochiasmatic, and in magnocellular parts of the supraoptic and paraventricular hypothalamic nucleus (PVH) in dehydrated but not euhydrated animals. However, CRH-ir neurons were decreased in the medial parvicellular part of the PVH. These results indicate that altered CRH mRNA levels previously reported in dehydrated animals translate into changes in peptide immunoreactivity. Copyright 1999 Elsevier Science B.V.